1. Field
The inventions relate to a flame retardant polymer composition that can be used to make molded articles with good physical and mechanical properties.
2. Description of the Related Technology
In general, rubber-modified aromatic vinyl resins show good processability, excellent physical properties, particularly, high impact strength and good appearance. Based on these advantages, rubber-modified aromatic vinyl resins have been widely applied to a variety of applications, including electrical and electronic products and office machines. However, these resins tend to burn out when they are applied to heat-emitting devices, such as computers and facsimile machines. Thus, methods for imparting flame retardancy to rubber-modified styrene resins are being developed.
A widely known method for imparting flame retardancy is the addition of a halogen-containing compound with an optional antimony catalyst. The inclusion of a halogen containing compound for flame retardancy may make the resin toxic. Therefore, non-halogenated compounds for use as flame retardants are desirable.
Other researchers have attempted to impart flame retardancy to rubber-modified aromatic vinyl resins by the addition of aromatic phosphates. However, this has resulted in the deterioration of physical and mechanical properties of the resin. In addition, the volatility of the phosphate results in impurities in the polymer resin. Since these compositions are also highly hygroscopic, special care is required in drying during processing when the composition is used as a flame retardant. In addition, molded articles manufactured from the composition by injection molding may suffer from deformation and serious variation in physical properties depending on the ambient atmospheric conditions, and thus there is a limitation in applying the composition to products.